Home

Awesome

sdc-headnode

This repository is part of the Triton Data Center project. See the contribution guidelines and general documentation at the main Triton project page.

This is the repository for building headnode images for Triton, and the initial setup and configuration of the headnode itself.

Quickstart (on OS X)

NOTE: As of 2021, one can also use the ISO installer on VMware or other virtualization platforms as long as the network interfaces are properly configured on VMware/other-virtualization for at least "admin" and "external".

To create a VM for local development work – commonly called 'coal' (Cloud On A Laptop) – follow these steps:

Less-quick start

There are four main build products from this repo:

Build prerequisites

On OS X (NOTE: OS X cannot make iso or ipxe):

On Linux (NOTE: Linux cannot make iso or ipxe):

On SmartOS:

First you must create a suitable build zone:

Then to set up the zone:

Build Specification: build.spec and build.spec.local

Some aspects of the configuration of the build, including which build artefacts will be included in the resultant Triton installation media, are specified declaratively. The JSON file build.spec contains the default specification of all build configuration, and is versioned in the repository.

During development, or as part of release engineering, particular elements of the build specification may be overridden in another file: build.spec.local. By re-specifying a subset of build configuration in this file, the behaviour of a particular build run may be altered. For example:

{
    "answer-file": "answers.json.tmpl.external",
    "build-tgz": "false",
    "coal-memsize": 8192,
    "vmware_version": 7,
    "clean-cache": true,
    "ipxe": false,
    "console": "ttya"
}

In the example above,

Build Artefacts

Two classes of build artefact may be described in the build specification file: zones and files.

Zones

The Triton headnode installation media includes images of various core zones. These zone images are are uploaded to a directory structure in Manta. Zone images are nominated for inclusion in the build via the "zones" key in build.spec.

The simplest possible example is a zone where the build artefact name is the same as the shipping filename, and the latest image is to be downloaded from Manta. One such example is the "adminui" zone:

{
    ...
    "zones": {
        "adminui": {},
        ...
    },
    ...
}

Some zones are known to the build infrastructure by one name, but shipped in the installation media by another (shorter) name. The build name can be provided with the "jobname" key on a per-zone basis. For example, the "manatee" zone comes from the "sdc-manatee" build name:

{
    ...
    "zones": {
        "manatee": {
            "jobname": "sdc-manatee"
        },
        ...
    },
    ...
}

Though the default source of zone images is Manta, the source may be overridden on a per-build basis with the "source" key. Zone images may be acquired from the IMGAPI service at updates.tritondatacenter.com by providing an image UUID, e.g.

{
    ...
    "zones": {
        "adminui": {
            "source": "imgapi",
            "uuid": "ef967904-fd86-11e4-9c90-2bbf99b9e6cf",
            "channel": "experimental"   // optional IMGAPI channel
        },
        ...
    },
    ...
}

Images may also be obtained from a local directory using the "bits-dir" source. The directory layout mirrors that of the Manta hierarchy used by other Manta/Triton components, and eng.git's "bits-upload.sh" script. If "bits-dir" is used, either through "source" for a specific zone or via the "override-all-sources" top-level key, the SOURCE_BITS_DIR environment variable must contain the path of a Triton release engineering bits directory. See the Triton release engineering documentation for details.

The above definitions will cause the download phase of the build to store a local copy of the zone dataset stream and manifest in the cache/ directory, using the original filename of the image, e.g. for manatee:

Note that the filename includes the build name and branch. A symbolic link will also be created to the downloaded files using the short name we specified, i.e.

In addition, any origin images of the zone image will also be downloaded and placed in the cache/ directory, e.g.:

Likewise, a symbolic link will be created to the download origin image files:

These symlinks are used by subsequent build phases to locate the downloaded build artefact.

Files

In addition to zone images and the base images on which they depend, the build also includes various individual files. These files are generally also the output of Manta or Triton component builds and are obtained either from Manta (by default) or a directory pointed to by SOURCE_BITS_DIR.

Files are specified in the "files" key of build.spec. For example, the Triton Agents are bundled together in a shell archive (shar) installer. This installer is produced as part of the agentsshar build. The shar itself is specified for inclusion with this entry:

{
    ...
    "files": {
        "agents": {
            "jobname": "agentsshar",
            "file": { "base": "agents", "ext": "sh" }
        },
        ...
    },
    ...
}

Note that "jobname" is used during the download to name the component because it is different from the short name of the file artefact itself, "agents". The download phase of the build will download file into the cache/ directory with its original file name, e.g.:

As with zones and images, a symbolic link will also be created for use during subsequent phases of the build:

By default, the "manta-base-path" top-level key is used to specify the base directory where the downloader will look for build artefacts in Manta. The default value for this key, as shipped in this repository, is "/Joyent_Dev/public/builds". If you wish to include an artefact that comes from a different Manta directory tree, you may specify the name of an alternative top-level build.spec key on a per-file basis via the following:

  1. Add a key with the value of the alternate Manta dir, e.g.:

        "my-private-manta-base": "/mymantauser/stor/builds"

  2. Specify "alt_manta_base": "<that added key name>" in the options for that file, e.g.:

        "files": {
        "sdcadm": {
            "alt_manta_base": "my-private-manta-base",
            "file": { "base": "sdcadm", "ext": "sh" }
        },
        ...
    },

    This tells the download phase to use your my-private-manta-base path for this artefact.

Alternative Branch Selection

By default, the build artefacts sourced for inclusion in the headnode installation media are from the master branch of their respective source repository. These build artefacts include the branch name in their file and directory names.

The default branch may be overridden by specifying the "bits-branch" key. The build branch for an individual zone or file may be overriden by specifying "branch" in the artefact definition. For example, to obtain artefacts from the release-20150514 branch for everything except the platform (and platform boot tarball) and cnapi zone, the following could be used in build.spec.local:

{
    "bits-branch": "release-20150514",
    "zones": {
        "cnapi": {"branch": "master"}
    }
    "files": {
        "platform": { "branch": "master" },
        "platboot": { "branch": "master" },
        "platimages": { "branch": "master" }
    }
}

As a convenience, the build will run bin/convert-configure-branches.js to convert configure-branches if it exists to a build.spec.branches file. This allows users to supply simple component and branch data in an simpler format. The above build.spec.local fragment would be written:

bits-branch: release-20150514
cnapi: master
platform: master

Note here, that since the platform, platboot and platimages artifacts and the agents and agents_md5 artifacts should always be matched. The tool that writes build.spec.local will include complementary values automatically. Any keys that do not map directly to a component (for example, bits-branch in the above snippet) are taken as top-level keys for the build.spec.branches file assuming that they're valid build.spec keys.

Note the build will merge build.spec, build.spec.local and build.spec.branches in that order into a file called build.spec.merged and will not report conflicting values across build.spec.* files.

Alternative build timestamp selection

By default, the build artifacts used for inclusion in the headnode installation from a given branch are obtained from a file named following the pattern buildjob-latest, which points to a manta directory named using buildjob-build_timestamp. Sometimes it is desirable to pick a different image than the most recently created one. On these cases, it's possible to specify the build_timestamp in build.spec.local:

{
    "files": {
        "platform": {
            "branch": "master",
            "build_timestamp": "20181024T220414Z"
        },
        "sdcadm": {
            "branch": "rfd67",
            "build_timestamp": "20171030T214543Z"
        }
    }
}

Feature Definition

The build specification allows for the build process to be different based on a set of named features. These features can be enabled or disabled by default, and may optionally be triggered by setting a nominated environment variable when the build is run.

For example, the build supports the use of either a release build or a DEBUG build of the operating system platform image. This feature is defined, under the top-level "features" key in build.spec, as follows:

{
    ...
    "features": {
        "debug-platform": {
            "enabled": false,
            "env": "DEBUG_BUILD"
        },
        ...
    },
    ...
}

The feature is named "debug-platform", and may be enabled via the DEBUG_BUILD environment variable. It may also be overridden in build.spec.local by specifying just the "enabled" property. For example, in build.spec.local:

{
    "features": {
        "debug-platform": { "enabled": true }
    }
}

Features are generally used to enable the conditional inclusion of particular sets of build artefacts, depending on the type of build.

Conditional Artefact Inclusion

Through the definition and activation of Features via the "features" key in the build specification, particular subsets of build artefacts may be included or excluded.

For example, the "debug-platform" feature is used to determine whether the release or DEBUG build of the operating system platform image is included in the build. Only one of these two platform images should be downloaded and included in the build.

{
    ...
    "files": {
        "platform": {
            "if_not_feature": "debug-platform",
            "file": { "base": "platform", "ext": "tgz" }
        },
        "platform-debug": {
            "if_feature": "debug-platform",
            "file": { "base": "platform-debug", "ext": "tgz" }
        },
        ...
    },
    ...
}

The "if_not_feature" directive causes the "platform" build artefact to be downloaded if, and only if, the "debug-platform" feature is disabled for this build. Conversely, the "if_feature" directive causes the "platform-debug" artefact to become active when a DEBUG build is requested. In this way, a selection between two different build artefacts may be made based on features. Feature activation is subsequently queried during later phases of the build through the use of the --feature (-f) flag to bin/buildspec.

Automating Headnode Setup: answers.json

The setup answers file, answers.json, provides information required for headnode setup that would otherwise need to be entered by the user into the interactive installer. Particularly for local development work, it can be convenient to specify some, or all, of this information in advance. The answers.json.tmpl and answers.json.tmpl.external files provide usable examples for local development; the former configures only the admin network on setup, the latter configures an external network as well.

The inclusion of a setup answers file in the resultant installation media is controlled by the "answer-file" key in the build specification.

Debugging build failures

Build logs are located in sdc-headnode/log/build.log.TIMESTAMP, and the logs of the latest successful build are symlinked at sdc-headnode/log/latest.

Setting TRACE=true in the environment will produce verbose output from bash. If you are using bash version 4.1 or later, you can combine TRACE with these environment variables for finer-grained control over trace output:

The build scripts also install an ERR trap handler that should emit a simple shell stack trace on failure, even when tracing is not enabled.

Debugging setup failures

Headnode setup is run by the /system/smartdc/init SMF service, and its logs can be accessed at:

[root@headnode (coal) ~]# svcs -L init
/var/svc/log/system-smartdc-init:default.log

The failure may have occurred in one of the zones being installed, rather than in the setup process itself. In that case, the relevant logs are often inside the zone (accessible via first zlogin $UUID):

Developing for the headnode

Development in this repo is typically to alter setup and bootstrap of the system. Setup scripts reside on a USB key or SmartOS bootable filesystem typically mounted at /mnt/usbkey, and are copied onto the headnode at /usbkey.

To test changes to setup procedures without a complete rebuild, you can:

Alternatively, one can use the ISO installer on a VMware machine (it can even be a replacement for CoaL).

<!-- References -->